Análisis modal con orientación hacia monitorización de salud estructural. Caso edificio Empresa Eléctrica Regional Centrosur

Abstract

The present research is focused on the study of the behavior of the building of the Empresa Eléctrica Regional Centrosur (EERCs), according to the modal parameters that govern its movement in the face of a seismic event, with a focus on the monitoring of structural health. For the analysis of the building, a structural survey is performed, focusing on the guidelines set forth in FEMA 154, starting with a visual inspection and determining the geometric dimensions of the structure. Then, the mechanical characterization of the building's concrete elements is carried out, 4 tests are performed (scanning of reinforcing steel, rebound number, extraction of concrete cores, resistance test) in the field and in the laboratory, focused on determining the concrete's resistance to compression; the influence of the nominal size of the coarse aggregate on the values obtained was determined. For the modal analysis, the structure is modeled by means of the program Etabs 17, seven models are proposed including gradual changes between these, depending on: the geometry of the building, the permanent loads such as walls and finishes, and the cracked sections of the concrete elements. In these analyses, the influence of the walls and cracked sections on the calculated vibration modes is studied. It was observed that generating loads on slab elements and the further away from the center of mass they are, the more flexible the structure becomes. Finally, for a study of an operational modal analysis, an instrumentation plan based on uniaxial, biaxial and triaxial sensors is proposed.